Reporters and conspiracy theorists were yesterday rifling eagerly through a mountain of fresh assassination-related documents in the hope of discovering a clue that was missed by years of police work, official inquiries, investigative books, television programmes, and public debate.
The National Archives in Washington released more than 800,000 papers about the murder, including 90,000 documents from the Central Intelligence Agency which - according to America's sizeable clan of conspiracy buffs, at any rate - could provide answers to some of those old but nagging questions.
For instance, was there a second gunman on the 'grassy knoll', another assassin who shot the president as his motorcade swept through the streets of Dallas in November 1963? Does the official 'magic bullet' theory really hold water? Was Lee Harvey Oswald working for the Mafia, or the KGB - or, indeed, a gang of conspirators within the the heart of the US government?
The archives disclosed the papers under a law passed last year which ordered the release of almost all the government's files about the investigation into Kennedy's death. The legislation followed years of public pressure, which intensified in 1991 with the release of Oliver Stone's JFK - a film which infuriated the establishment by suggesting the assassination was an elaborate government plot.
As well as the stack of CIA papers, the documents include material from the FBI, US State and Defense departments, presidential libraries, and the Warren Commission - the much-criticised official inquiry which concluded that Kennedy was killed by a single bullet fired by Lee Harvey Oswald. But it was not immediately clear what, if any, fresh evidence would emerge.
Some of the papers have already been winkled out into the open by legal action or under the Freedom of Information Act. Other possibly critical material remains under wraps under an exemption clause. This covers records that would identify 'an intelligence agent whose identity currently requires protection' or sources who would be at risk of harm.
Anyone expecting a revelation within the first few hours of their release will have been disappointed yesterday. The only titbit of any passing interest was a memorandum written five days after the assassination in which a CIA officer speculated that the murder was instigated by the KGB in an attempt to relieve the domestic pressure on the then Soviet leader, Nikita Khrushchev.
Investigators say that more than half of the documents on the assassination remain unpublished.